Over center toggle mounting of plow



United States Patent [111 3,53

[72] lnventor Roger W. Woelfel 3,032,122 5/1962 Geurts 172/264 3780 S.Woelfel Rd., New Berlin, Wisconsin 3,191,688 6/1965 Morkoski et a1172/269 53157 2,411,072 11/1946 Washburn 172/234X PP; 33 1 1967 FOREIGNPATENTS [221 File 557 433 11/1943 Great Britain 172/267 [45] Paemed 1970635,406 1/1962 Canada 172/264 Primary Examiner-Robert E. Pulfrey 54 OVERCENTER TOGGLE MOUNTING 0F PLOW Assisi! Examiner-Alan Kopecki 15 Claims,4 Drawing Figs. Att0rneyWheeler, Wheeler, House and Clemency [52] [1.8.CI 172/234, m

Z/2 172/266 ABSTRACT: Disclosed herein is a self-restoring plow having a1111- Cl a a 61/04 'tool standard pivotally mounted on a bracket whichis [50] Field ofSearch 42 moumed f pivotal motion on a plow frame with ahydraulic 74/520, 521 cylinder connected to return or bias the bracketto an opera- I tive position. A linkage system in the form of a strap iscon- [56] References cued nected between the tool standard and the plowframe to pivot UNITED STATES PATENTS the tool standard independently ofthe bracket as the bracket 2,109,385 2/1938 Garrison et a1. H 172/267moves toward an inoperative position. The linkage system can 2,544,8153/1951 Weaver 172/166X also include a pair of links or straps forming atoggle element 3,302,728 2/1967 Sullivan et a1, 172/265 connectedbetween the bracket and the frame with the 3,321,027 5/1967 Johnson etal. 172/266 hydraulic cylinder connected to bias the toggle elements toan 3,321,031 5/1967 Evans 172/605 oncenter position with the toolstandard strap connected to 3,420,315 1/1969 Roth 1 172/265 the toggleelement so that the initial motion of the tool stanl,892,978 l/l933Burch 172/264 dard will move the toggle elements off center.

OVER CENTER TOGGLE MOUNTING OF PLOW BACKGROUND OF THE INVENTION When themoldboard on a plow strikes an object in the ground, it must moverapidly to a position clear of the object or the moldboard will bedamaged. A number of spring actuated and hydraulic release arrangementsare presently available which can produce this result but have not beenreadily accepted because of the relatively horizontal motion of themoldboard in moving to the inoperative position and the fast returnmotion. Most of these arrangements merely allow for a pivotal motion ofthe tool standard for the moldboard against a return force of a springor hydraulic cylinder. If a spring is used, the return forces exerted bythe spring will often snap the tool standard back so fast that themoldboard throws stones past the operator. Where toggle elements havebeen used to provide a snap-type release of the bracket for the toolstandard for the moldboard, the initial motion of the moldboard in bothleaving and entering the ground is substantially horizontal.

SUMMARY OF THE INVENTION The self-restoring plow of the presentinvention operates either on an accelerated motion or a snap releasemotion in order to clear the moldboard from the ground after engaging anobject. The plow in either instance includes a tool standard having amoldboard secured to the lower end of the standard with the standardpivotally mounted on a bracket that is free to pivot about a pin on theplow frame. A link or strap is connected to the upper end of the toolstandard and to the frame to hold the upper end of the tool standardsubstantially in a fixed position whenever the bracket pivots about thepin in the frame. The tool standard rotates or pivots at a faster ratethan the motion of the bracket, pulling the moldboard rapidly from theground. The motion of the bracket is resisted by a hydraulic system thatallows for fast release of pressure when the.

moldboard engages an object and a gradual return of the bracket to anoperating position. In the snap release system a linkage which includestoggle elements is connected between the frame, the bracket and thehydraulic cylinder. The hydraulic cylinder is used to restore the toggleelements to an oncenter position as soon as the pressure is relievedfrom the end of the moldboard. The strap or link for the tool standardis connected to the toggle elements to provide an initial pull on thetoggle elements toward an off-center position so that the bracket isfree to pivot upward upon engagement with an immovable object. Thecolter for the plow can also be pivotally mounted on the plow frame andconnected by a release bar to the toggle elements in the linkage toprovide an initial offcenter motion for the toggle elements in the eventthe colter engages a stone or other immovable object.

Other objects and advantages will become apparent when the followingdetailed description is read in connection with the accompanyingdrawings in which:

FIG. 1 is a side view partly in section of a dual pivot plow.

FIG. 2 is a side view of the dual pivot plow with a snap releaselinkage.

FIG. 3 is a view of the plow of FIG. 2 with the plow in the trippedposition.

FIG. 4 is a view ofa modified snap release linkage.

Although only a few embodiments of the present invention are disclosedherein, it should be apparent that various changes and modifications canbe made without departing from the scope of the following description ofthe invention.

Referring to FIG. I of the drawings, the supporting frame 10 for amultipletype plow is shown with a double beam 12 extending rearward tosupport a plow 14. Generally in a multiple plow arrangement, there areas many as five beams extending rearward from the supporting framelO. Achannel member 11 extends across the rear of the beams 12 to hold thebeams in a spaced relation. A support bracket 15 is pivotally mounted ona pin 16 between beams 12 with a tool standard 18 pivotally mounted onpin 20 on the lower end 22 of the bracket. A working tool moldboard 21is secured to the end of the tool standard. Means in the form of a linkor strap 26 is connected to the upper end of the tool standard 18 by apin 28 and to the inside of one of the beams 12 by a pin 30 to pivot thetool standard relative to the bracket. As seen dotted in FIG. 1, whenbracket 15 pivots upward about pin 16, the tool standard 18 will pivotrapidly about pin 20 due to the force applied by strap 26 against theupper end of the tool standard. The end of the moldboard will swingrapidly in an arc rearward relative to the beam of the plow. This meansthat relativeto the ground the forward motion of the plow has stoppedwhile the moldboard is being raised out of the ground.

The upward pivotal motion of bracket 15 is restricted by means of ahydraulic piston assembly 32 having cylinder 33 connected to anupstanding frame member 34 by a pin 35 and piston rod 36 connected tosupport bracket 15 by pin 37. The piston 38 in cylinder 33 operates in amanner as disclosed in my copending U.S. Pat. application Ser. No.669,497, filed September 21, I967, which yieldably affords pivotalmovement of the moldboard or working tool by the fast release ofpressure from cylinder 33 through pressure line 29 on the application offorce to piston rod 36 by the upward motion of the bracket when themoldboard engages an object. The bracket 15 is biased to return to itsoriginal or operative position by the buildup of pressure behind piston38 in cylinder 33 as soon as the moldboard clears an object and thepressure on the moldboard is reduced. It should be noted that on thereturn motion of the bracket 15 to its original or operative position,the point of the moldboard will enter the ground at an angle rather thanbeing horizontal. This means that penetration of the point of themoldboard will occur immediately. The link or strap 26 will cause thetool standard to move simultaneously with the motion of the bracket 15and at a faster rate in moving back to its original position. A limitstop 13 is secured to the beams to limit the downward position of thebracket.

The self-restoring plow of FIGS. 2 and 3 also includes a pair of beams12 extending rearward from frame 10. Support bracket 15 is mounted topivot between the beams on pin 16 and tool standard 18 is pivotallymounted on pin 20 as described in FIG. 1. Means are provided to hold thebracket 15 in a fixed position when the moldboard is in the operative orplow position in the form ofa linkage assembly 39 which includes toggleelements 40 and 42. Toggle element 40 is con nected to bracket 15 by pin41 and toggle element 42 is connected to fixed frame members 44 and 46by pin 43. The toggle elements are connected together by pin 48 and inthe oncenter position will prevent upward movement of the bracket 15.Piston rod 36 in hydraulic assembly 32 is also connected to pin 48 andholds the toggle elements 40 and 42 in the oncenter position by theengagement of piston 38 with the front of cylinder 33.

Means are provided to move the toggle elements 40 and 42 off center whenthe moldboard 21 on tool standard 18 engages an object, such as a stoneor log allowing the tool standard to pivot about pin 20. Such means isin the form of the strap 26 which is connected to the pin 48 on thetoggle elements. This initial motion of the toggle elements 40 and 42will allow for a small amount of play in the motion of the tool standardbefore the bracket moves. As soon as the toggle elements 40 and 42 aremoved off center, the bracket is substantially free to pivot upward onpin 16 until the moldboard clears the object as seen in FIG. 3. When thepressure is released from the tool standard, pressure will build upin-hydraulic cylinder 33 pushing the piston rod toward the on-centerposition of the toggle elements. The moldboard will again enter theground at an angle sufficient to penetrate the ground. The motion of themold board will be substantially the same as in FIG. 1; that is, themoldboard will swing in an arc rearward relative to the plow.

If an object is lying on or near the top of the ground, it is desirableto have the bracket ready to move freely around pivot pin 16 prior tothemoldboard engaging the object. This is accomplished by using colter50 as a means to move the toggle elements off center before themoldboard engages the object. The support 51 for colter 50 is clamped toa bracket 52 by clamps 54 and bolts 56. The bracket is mounted to pivotabout pin 58 in beams '12. A link or release bar 62 is connected tobracket 52 by pin 64 and to pin 48 of the toggle elements. When thecolter engages the object and pivots about pin 58, link 62 will bepulled forward, moving the toggle elements off center. A slot 66 isprovided in link 62 to allow the bracket to pivot independently of thecolter.

In a multiple-type plow, it often becomes necessary to raise one or moreof the plows out of the ground because the ground is too heavy or wetfor the tractor topull the five plows. A notch 55 is provided on the topof beams 12 behind bracket 15 and on raising thebracket, a pin (notshown) can be placed in the notch to engage shoulder 59 on the bracketpreventing its return to an operative position. The pin and notch 55 canalso be used to hold the bracket up when the moldboard is changed on thetool standard. If the depth of 1 penetration of the plow has to bechanged at any time, an eccentric pin may be used in place of pins 43and 41, and on' rotation of the eccentric pin the toggle elements can beshifted up or down with respect to the frame with a corresponding 7change in the location of the moldboard.

in the modificationshown in H0. 4, the bracket 80 is pivotally mountedon pin 82 on beams 12. Tool standard 18 is mounted on pin 20 on thebracket and supports a moldboard connected to lever arm 84 by pin 98.Slot 85 in lever arm 84 allows for limited amount of lost motion betweenthe lever arm and piston rod. The pivotal motion of the bracket islimited by meansof a linkage assembly 39 which includes a toggle element40 connected to the bracket 80 by pin 41 and a toggle'element 42connected to the frame 88 by pin 43 and to the toggle element 40 by pin48. A connecting link 102 is connected to lever arm 84 by pin [04 andtoggle element 42 by pin 106. When lever arm 84 is pivoted toward frame88, link 102 will push toggle elements 40 and 42 off center which allowsbracket 80 to pivot freely about pin 82. A slot 100 is pro- .vided inconnecting link 102 to allow the tool standard to move initially againstthe piston without moving the toggleelement off center. A colter releasearrangement can also be used with this modification to move thetoggleelements off center.

It should be obvious that the above described arrangement can be usedwith any earth working implement.

If the strap 26 is secured to the frame in F IG. 2, the toggle elementsshould be in an off center relation in order to allow the bracket topivot. This can be accomplished by moving pin 35- in cylinder-33 to oneof the alternate holes 25 in frame member 34 to pull piston rod 36 andpin 48 away from the oncenter position.

lclaim:

1. A self-restoring plow comprising a support frame, a

' bracket directly pivotally connected to said support frame for amovement from an operative to an inoperative position, a.

moldboard standard pivotally supported on said bracket, a moldboardconnected to said standard, linking means pivotally connected to saidstandard and to said support frame to afford rearward displacement ofsaid moldboard about said pivotal connection of said bracket and saidsupport frame and about said pivotal connection of said bracket and saidstandardupon tripping of said plow, and means connected to said frameand to one of said bracket and said standard, said lastnamed means beingyieldable under force for biasing said bracket to the operative positionon said frame.

2. A self-restoring plow according to claim 1 including a linkageassembly having first and second toggle elements, said toggle elementshaving adjacent ends, means connecting said adjacent ends of said toggleelements, the opposite ends of said toggle elements being connectedbetween said frame and said bracket, said toggle elements being movablebetween off center and on-center positions to afford tripping of saidmoldboard, said biasing means being connected to bias said toggleelements toward said on-center position.

3. A plow according to claim 2 including a colter pivotally mounted onsaid frame and a colter-release bar pivotally connected to said colterand pivotally connected to said toggle elements to move said toggleelements off center when said colter strikes an object.

4. A plow according to claim 2 wherein said biasing means comprises ahydraulic piston assembly connected between said frame and said toggleelements.

5. A self-restoring plow comprising a support frame, a bracket pivotallyconnected to said support frame for movement from an operative to aninoperative position, a moldboard standard pivotally supported on saidbracket, and means yieldable under force for biasing said bracket to theoperative position on said frame, a linkage assembly having first andsecond toggle elements connected between said frame and said bracket,said toggle elements being movable between off center and on-centerpositions, said biasing means being connected to bias said toggleelements toward said oncenter position, and linking means connectingsaid standard to said toggle elements so that the motion of themoldboard supporting standard on engaging an objectwill move said toggleelements off center against the bias of said bias means.

6. A self-restoring plow according to claim 1 wherein said linking meansfor connecting said standard to said support frame includes two commonlyconnected links. one of said links being connected to said standard andthe other of said links being connected to said frame, and wherein saidmeans yieldable under force is connected to one of said links.

7. A self-restoring plow comprising:

a frame;

a support bracket pivotally mounted on said frame and movable from anoperative position to an inoperative position; a

a linkage assembly including toggle elements movable between on-centerand off center positions connected between said frame and said bracket:

means for hydraulically biasing said toggle elements toward an on-centerposition to move said bracket to an operatlve position;

a tool standard pivotally mounted on the bracket; and

means for connecting said tool standard to said toggle elements to movesaid toggle elements off center on pivotal movement of said standardrelative to said bracket.

8. A plow according to claim 7 wherein said means for connectingincludes:

a lever arm pivotally connected to said frame;

a link connected to said standard and to said lever arm; and

a connecting link connected between said lever arm and said toggleelements.

9. A self-restoring working tool comprising:

a support frame;

a bracket pivotally mounted on said frame;

a tool-carrying standard pivotally connected to said bracket;

a linkage assembly connected between said frame and said bracket, saidlinkage assembly including:

a pair of toggle elements movable between off center and on-centerpositions;

hydraulic means for biasing said toggle elements to an oncenter positionto prevent pivotal motion of said bracket; and

a link connected between said standard and said toggle elements whereinpivotal motion of said standard will move said toggle elements offcenter to allowpivotal motion of said bracket.

10. A self-restoring plow according to claim 9 including:

a colter pivotally mounted on said frame; and

a release strap connected between said colter and said toggle elementswhereby said colter will move said toggle elements off center when saidcolter engages an object.

11. A self-restoring type plow comprising a frame, a bracket pivotallymounted on said frame, a plow-carrying standard pivotally connected tosaid bracket, a pair of toggle elements connected between said bracketand said frame and movable between off center and on-center positions topivot said bracket between operative an inoperative positions, means forbiasing said toggle element toward an on-center position, a lever armconnected to said frame, a link connecting said standard to said leverarm, and means connecting said lever arm to said toggle elements to movesaid toggle elements off center when said standard pivots on said frame.

12. A self-restoring type plow according to claim 11 wherein said meansconnecting said lever arm to said toggle elements includes a connectinglink, a slot in said connecting link and a pin extending through saidslot and connected to said toggle elements.

13. An agricultural implement comprising a frame, a bracket, means forpivotally connecting said bracket to said frame, a standard, a workingtool connected to said standard, means for pivotally connecting saidstandard to said bracket at a point intermediate the ends of saidstandard, a rigid link having one end connected to said standard at apoint spaced from said pivotal connection of said standard and saidbracket, the other end of said link being connected to said frame at apoint spaced rearwardly of the pivotal connection between said standardand said bracket to afford rearward pivotal movement of said workingtool relative to said bracket upon pivotal movement of said bracketrelative to said frame as said working tool encounters severe draftpressure.

14. A self-restoring plow comprising a support frame. a

bracket pivotally connected to said support frame for movement from anoperative to an inoperative position, a moldboard standard pivotallysupported on said bracket, means for connecting said standard to saidsupport frame, means yieldable under force for biasing said bracket tothe operative position on said frame, a linkage assembly having toggleelements connected between said frame and said bracket, said toggleelements being movable between off center and on-center positions, saidbiasing means being connected to bias said toggle elements toward saidon-center position, said biasing means comprising a hydraulic pistonassembly connected between said frame and said toggle elements, andmeans for moving the connection of said hydraulic piston assembly tosaid frame whereby said toggle elements are maintained in an off centerposition.

15. An agricultural implement comprising a frame, a working tool, meansfor supporting said working tool on said frame, said means including abracket and a standard, said working tool being connected to saidstandard, means for directly pivotally connecting said bracket to saidframe to form a first pivotal axis for said working tool, means forpivotally connecting said standard to said bracket to form a secondpivotal axis for said working tool means connected to said frame andpivotally connected to said means for supporting said working tool foryieldably biasing said working tool to the operative position from thetripped position to afford pivotal movement of said working tool aboutsaid first and second pivotal axes as said working tool encounterssevere draft pressures, and linking means pivotally connected to saidstandard and pivotally connected to said frame to afford rearwardangular displacement of said working tool relative to said bracket upontripping of said working tool from the operative position.

